The Reno Gazette-Journal reported that U.S. Attorney Daniel Bogden sent a letter to the Moapa Paiute chairman noting that the “transport, possession, use and distribution of controlled substances, including marijuana” is prohibited by federal law.

The letter references the 2013 Cole Memo, an Obama-era directive that gave federal prosecutors and law enforcement guidance in states where marijuana has been legalized, on how to best prioritize their efforts regarding enforcement of federal marijuana laws. Bogden writes:

I am informed that the tribal council is moving forward with the planned marijuana event referred to as the 2017 High Times Cannabis Cup because it is under the impression that the so-called ‘Cole Memorandum’ and subsequent memoranda from the Department of Justice permit marijuana use, possession and distribution on tribal lands when the state law also permits it. Unfortunately, this is an incorrect interpretation of the Department’s position on this issue.

Moreover, both the Guidance Memorandum and the Cole Memorandum to which it refers explicitly state that even where none of the listed factors are present, federal investigation and prosecution may still be appropriate. Nothing in either the Policy Statement or the Cole Memorandum alters the authority or jurisdiction of the United States to enforce federal law in Indian Country.

The High Times Las Vegas Cannabis Cup comes just months after Nevada voted in favor of legalizing recreational, adult-use marijuana.

“High Times and The Cannabis Cup are always working hard to help people exercise their legal rights – from freedom of speech to the right to assemble peacefully,” organizers of the Cannabis Cup said Wednesday in a statement to The Cannabist. “We do so in cooperation with all local, state and federal laws and in partnership with local law enforcement.”

However, as reported by the Reno Gazette-Journal, High Times also has suggested that participants might be wise to leave their marijuana at home, given the feds’ warning:

“But now federal authorities have intervened directly with our host venue, the land of the Moapa Band of Paiutes. Subsequently, we’ve been informed that our upcoming Cannabis Cup event in Nevada on March 4-5 can proceed as planned, but vendors, guests, performers and attendees are advised to comply with all local, state, and federal laws regarding the use and distribution of cannabis and cannabis related products.”

A spokesman for the Moapa Paiute tribe told the Las Vegas Sun that this weekend’s event, the first Cannabis Cup to be held on U.S. tribal lands, is expected to bring in around 15,000 people as well as 300 vendors from 15 countries.

The 2017 High Times Cannabis Cup – Nevada is scheduled for March 4-5. The Cup will be held across the street from the Moapa Paiute Travel Plaza: